羟氯喹在人肝微粒体CYP酶中的代谢研究

Enzyme Kinetics Research of Hydroxychloroquine in Human Liver Microsomal CYP Enzymes

目的:探讨羟氯喹在人肝微粒体中的主要代谢酶及其代谢特点和参数。方法:建立高效液相色谱-荧光检测器(HPLC-FLD)测定孵育液中羟氯喹的方法,观察9种CYP酶特异性抑制剂对羟氯喹代谢的影响,计算羟氯喹的酶促动力学参数如米氏常数(K_(m))、最大反应速度(V_(max))和药物的内在清除率(C_(Lint))。结果:9种酶抑制剂中孟鲁司特(CYP2CB抑制剂)、酮康唑(CYP3A4抑制剂)、噻氯匹定(CYP2B6抑制剂)能够显著抑制羟氯喹的代谢(P<0.05)。羟氯喹在人肝微粒体中Vmax为233.6 ng·mL^(-1)·h^(-1)·mgprotein^(-1),Km为14.5 ng·mL^(-1),CLint为16.2 h^(-1)·mg-1protein。结论:羟氯喹主要通过CYP2C8、CYP3A4和CYP2B6代谢,药物在体内清除速率慢,药物相互作用和蓄积是发生不良反应的重要因素。

Objective:To investigate the metabolic characteristics and enzymes of hydroxychloroquine in human liver microsomes.Method:An HPLC-FLD method was used to determine the concentrations of hydroxychloroquine in incubation liquids.Changes of hydroxychloroquine metabolism were observed with 9CYP subtype specific inhibitors.Enzymatic dynamics study of hydroxychloroquine was also calculated to deduce drug Michaelis constant (K_(m)),maximum reaction rate (V_(max)) and drug clearance (C_(Lint)) in vitro Results:Among the 9 inhibitors,ketoconazole,montelukast and ceclopyridine significantly inhibited the metabolism of hydroxychloroquine.The values of K_(m),V_(max)and C_(Lint)of hydroxychloroquine in hepatic microsomes were 233.6 ng·mL^(-1)·h^(-1)·mg-1protein,14.5 ng·mL^(-1)and 16.2 h^(-1)·mg-1protein,respectively.Conclusion Hydroxychloroquine is mainly metabolized by CYP2C8,CYP3A4 and CYP2B6.The rate of drug clearance is slow.As a result,drug interaction and accumulation are important factors for adverse effects.